Feeding mechanism for sewing machines



Oct. 5 1926. 1,602,145

S. W. AVIS FEEDING MECHANISM FOR SEWING MACHINES Original Filed July 1, 1920 3 Sheets-Sheet I Arm/Mfr Oct. 5 1926.

- s. w. AVIS FEEDING MECHANISM FOR SEWING MACHI NES Original Filed July 1. 1920- S-Sheets-Sheet 2 Oct. 5, 1926. 1,602,145

' S. W. AVIS 1 FEEDING MECHANISM FOR SEWING MACHINES Original Fild July '1, 1920 s Sfieets-Sheet Patented Get. 5,1 32%.

smear. w. A'vrs,}onwnsr HARTFORD, oon'nncrrcnr.

FEEDING MEcnANrsM'Fon snwme MACHINES.

Original applicationfiled July 1, -1920,SerialNo. 393223.- *Ditrided eindthis application filed August 2',

' -1921, "serial'Nop lsfififi. Renewed March 12, 1928. t

This inventionrelatesparticu'larly to the carrier and a part ofits reciprocating mechfeeding mechanism of those sewingma-- anisni. Fig. 8shows aplanof the feed dog chines which have aneedleand-two loopers carrier reciproc-atingyoke. Fig. 9 is awverthat stitch with two or three threads and tical section through-rthe-feed dog oscillat- 5 are commonly known as overseam machin'es, ing mechanism lon the plane indicatedby 60 such a machine heingzset forth inapplicathe dotted line 9 -9 on Fig. 3. "Fig; 1 0 tion No. 393,223 filed-by me July l, 1920, shows the feed dogs, their carriers and top fromwhich-application the-subject of this retaining plate separated. i application has been divided. 'i'In the machine "illustrated thee: needle,

lhe object of the invention is to provide looper's', feed dogs-and'trimmer are all-actu- 65 a suitable w'ork feed ing mechanism for ated froma single rotatory shaft-1 which machine of this class iii-which the mechais supported below the work iplate 2 with nismsare simple, cheap', a1i d durable,- are its-aXisparallel-with theline'feed oiitlie easily adjusted so the machine will be capawork to be stitched on the m'achine. This ble of stitching a large variety ofworlg-are shaftis supported nearone 1 end bywa-nti- W: located so as to permit maximum freedom in friction bearings 3,- near th e'mi-ddle by antithe manipulation of the workfand' arede friction bearings kand nearthe other-end signed so they can run at very high'spee ds by antifriction bearingsih held in'a'eastiron with a minimum expenditure oi: power'and skeleton bed frame 6 WhlCh lS' QDClOSQd in 1 without objectionablevibration, and produce a tight casing 7 that'is ad apted to hold 7 a stitch "of desired niformity I on differentsupply of lubricant. 011 the end-'ofthe shaft thicknesses (if-material. j I outside the casing is af-pulley 8 which may 'These objects are attained by designing he driyen by a 'belt or'motor-- as desired," the mechanisms which actuate the stitch Fig. 3. I v W forming needle and loop'ers, and the co-oper- Iii the interiorof=the easing the; shaft ating work controlling it'eed dogsfpresser carries a drum 9 withia 'canrgroov 10in its foot and trimmer so 'that'there are no unperiphery. Lying in this cam grooveis a necessary parts and motions, but few rectiroll 11 on the lower' end ofthe lever 12 which linear movements, and s'liort-reciprocatory projects'down'ward within-the casing jifrom, movements, andarranging such;- operative and isclamped to a'squ'are'd section of one mechanisms in substantial bearin'g's'on firm end- '01 the conical arbor 13 thatis fitted in support which will absorb vibration, below l'ongitaperingbearing in the needle'carrier the workplate whereithey are out otthe blockl kwhich 'ls secured'to the top'ofthe way and can be entirely enclosed in a tightbedframaFigs. 3, 4. Extending upwardly dust and lint excluding casing'which wlll fromthe" other end ofthe'arborthrough the; 970

hold oil and thus permit free splashzlubriblock and a slot in'thework plate, ;is'=a= needle cation of all joints and surfaces in frictional carrierlathe upper end of which carries contact, thereby eliminating as'muchas pos the curved needlje- 116 that is clamped in sible objectionable inertia forces and fric place byjthe screw 17'. 1 The cam grooyeis tion'and-permitting the machine to be run soshaped'that it oscillates the-needle-car 95 at a very high speed with 'butslight wear. rier at the proper intervals to swing the In the accompanying drawings, Figure 1 needle point down through and return it; shows a side elevation of amachine pro-y out ofthe usual openingin-the. need-1e plate vided with the teed'ng' mechanism which 18 that is set flush'withthe work plate. embodies this invention. Fig. "2 shows a Theoscil'latory movement ofgthe need-leaf front elevation of thesame. Fig; 3 shows on bor is slight. and the bearing is long-so that larger scale, a Vertical section on the plane there isslight 'fr iction 'andwear between of the cam shaft as'indioated bythe dotted these parts. line 33 on Fig. l. Fig. 4' shows a plan of In theend-fa-ce ofthe "druiirQfiis a cam 50 the mechanism with the work plate removed, groo'ye 19 and lying inthis'fgrooye are rolland portions broken away. "Fig. 5 is a e rs 20 and 21 oh the ends of short-1 rocker vertical section on dottedline-5-5 on Fig. arms 22 and 23 1 which project -.fm1athe 4:] Fig. 6 is'a Vertical section on dotted looper carrie'rspjQtan'df25i .gThe-looper.car- A line 6-6 on Fig. 3 with parts broken awayri ers are-preferably conical with collars 2 6 i Fig. 7 isayiew of the front feed dog its neartheir'largerends and they are located bed frame, Figs, 3,

in tapered hearings in the looper carrier block 27 that is fastened to the top of the The loopers 30 and 31 pass from the carriers through an opening 34 near the end of the looper carrier block which opening is opposite. portions of the journal bearings at the larger ends of the carriers and not open to the interior of the casing so that lubricant cannot escape through the opening. rin opening 33 is made through the side of the casing so that the carrier adjusting and clamping nuts and the looper clamping screws can be reached by a wrench and this opening is covered by a plate 35 that is fastened to the casing, Figs. 5, 9. The. rocker arms are very short andthe loopers are long, consequently the looper carriers have but little oscillatory motion and as the carrier bearings are long the carriers can be run very rapidly with but slight friction'and Wear and the wear if any can be easily taken up. The needle swings down and up through the needle opening in the needle plate'in a plane parallel with the line of .feed while the loopers oscillate in planes transverse to the line of 7 feed, the lower looper oscillating below the needle plate and the upper looper swinging from beneath around one side over the top of the needle plate.

On the shaft 1 near one end is a cam 36 which actuates the front toothed feed dog 37 and the rear toothed feed dog 38, Figs. 3, 6, 9. This single cam through the. connecting mechanisms imparts a longitudinal reciprocatory movement forwardand back to the feed dogs and gives them a transverse oscillatory movement so they are raised up through the needle plate when forward and lowered below the needle plate when back. The rear feed dog is attached to a carrier 39 which has a cylindrical under surface that fits in a correspondingly shaped cavity formed in the top of the feed dog block 40 secured to the top of the looper carrier block Fig. 5. Projecting downward from the rear feed dog carrier in front of the feed dog block are a pair of lugs 41, into the opening between which extends a tooth 42 projecting upward from ,a fork 4-3 that is mounted on a stud 44 projecting from the raised front end 45 of the bed frame, Figs. 3, 9. This fork straddles the cam so that the rotation'of the cam oscillates the fork and causes the rear feed dog carrier to rock on its longitudinal axis.

The front feed dog is attached to a carrier 46 which has an angular lower surface that fits in an angular cavity in the top of the rear feed *dogcarrier. The upper surf-ice of the front feed dog carrier has a cylindrical cavity and fitting in this and retaining the carrier in place is a plate 47 that is fastened to the under side of the work plate, Figs. 3, 9, 10. The under curved surface rear feed dog carrier.

of the rear feed dog carrier and the upper curved surface of the front. feed dog carrier are concentric the center being'prefenably above the work plate. As a result of this construction'the front feed dog carrier is oscillated with the rear feed dog carrier, but is free to be. moved longitudinally independently of the rear feed dog carrier. The oscillatory movements, the axis of which is preferably above the work plate, are small and the bearings are long, consequent ly the wear is slight and there is but little inertia to overcome, so the parts may be. op-' intoan opening between two arms which project from the bottom of the yoke and as 'sists in guiding the yoke. The connections between the yoke and feed dog carriers similarbut independently adjust-able. The yoke on each side has a rolle 51 which occupies a radial slot 52in the face of an adjustable bell crank plate 58 that has a long tapering arbor "4, Figs. 6, 7. Each ofthese arbors is mounted eccentrically in a cylinder- 55 that is rotatably located in an opening in a hub 56 projecting in from the side of the casing. At the outer end of each cylinder in an opening in the casingis a disk with a handle 58, and thrusting between the cylinders and disks are springs 59. The cylinders and disks have flanges 60 and are frictionally retained in position by plates 61 fastened to the casing" outside of the flanges, Fig. 6. By means of the handles the cylinders may be rotated in order to change the angular relations of the axes of the bell crank plates to the axes of the rollers on the yoke which engage and oscillate the crank plates as the yokemoves up and down.

Lying in a curved slot 62 in the face of each crank plate is a roller 63 on an lever 64, Figs. 6 and 7. a solid arbor 65 and the other a tubular arbor 66 that surrounds the solid arbor and is fitted in a bearing in the upwardly ing end 45 of the bed frame, Figs. 3, 6. The lever on one side at its upper end has a roller 67 engaging between the wallsof an opening 68 in the side near the front end of the V The angle lever on the other side at its upper end has a roller 69 engaging between the walls of an openangle ing 70 .1 the side near the front end of the One angle lever has extend lil) practically oscillating ca'm segments which form connections or links between the yoke.

which oscillate the angle levers that'reciprocate the feed dogs. By turning the cylinders which support thearbors of the bell crank plates and changing the angular relations of the axes of the plates to the axes of the rollers carried by the yoke the recipi'ocatory movements of the feed dogs maybe altered at any time without interfering with the running of the machine. WVith the mechanism described the amount of feed of the dogs and the relations of the movements of the dogs to each other may be varied independently as desired, according tothe character of the work being operated upon.

. The trimmer has a blade 73 which normally is stationary, and a co-operating blade 74 that oscillate-s with relation to the fixed blade for trimming the edge'of the material that is being fed beneath the needle, Fig. 5. These blades are mounted in such manner that they may be adjusted more or less to one side of the plane of the needle or line of stitch or swung-over away from the front of the needle and loopers as fully described in'the application from which tliiS'Was di-.

The fixed blade is curved and is clamped in a-groove in the housing 7 5. The oscillatory blade is a curved plateclamped in'a curved slot in the head of a rocker arm 81 which projects from a shaft 82. The housing has a projection '89 that is hinged to a link which is provided with vicled.

a handle 91 and is pivotally mounted on a plate 92 secured to the ca's'i'ng,'Fig. 5. By

turning be ad usted as mentioned;

The presser foot 95 is pivotally mounted on the lower end of a finger 96 which is hinged to the end 'of an arm 97 that is'pivoted to the side wall of a cover 98 that is above the work plate on one side near the rear of the machine. A spring'99 holds the presser foot down. spring is regulated by a scre'wlOl.

Secured to the front end of the cam shaft is a disk 1'02, thatit will dip into lubricant in the bottom of the casing and thro-w'it onto the active mechanisms in the front of the machine.

The feed of the dogs'may be independently varied according to the material to be stitched and the seam tob-e made which feed.

may be changed as is necessary "at any time to prevent the material from orfrom being'puckered while stitched; -By operating the feed dogs transversely at the end of the feed stroke theirteeth a're gaged from the material or any loose fibers the handle the trimming blades may The tension of this Fig. 3, of'such size and shape being stretched disenwithout 'dangerof' drawing back and cans-- ing the material to wrinkle.

The invention claimedis: 1

1. In a sewing machine the combination with the stitch forming means, of a feed ing mechanism comprising a front feed dog, a rear feed dog, means for reciprocating the do s in rectilinear paths, and means forosciliating the dogs on .an axis parallel with said paths. 2

2. lnqa'sewing machine the combination with thestitch forming means, of a feeding mechanism comprising a front feed dog, a rear feed dog, means for reciprocating the feed dogs independently in rectilinear paths,

and means for oscillating the feed dogs coin- ,mechanism, mechanism for reciprocating the rear feed dog, means for adjusting the feeding movement of the rear feedfdog mechanism and mechanism for oscillating the feed dogs at right angles to their reciprocating movements atrthe ends ofsaid movements.

= 4. In a sewing machine the combination with the stitch forming means, of a feed mechanism comprising a front feed dog, a

rear feed dog, mechanism for reciprocating the front feed dog, means foradjustin'g'the feeding movement of *the'front feed dog mechanism, mechanism for reciprocating the rear feed dog,'meansfor adjusting the feeding movement of the rear feed dog mech aiiism, and mechanism for oscillatingthe feed dogs on an axis parallel with their reciprocating paths.

5. In a sewing machine the combination withthe stitch forming means, of a feeding mechanism comprising two feed dog carriers, independ'ently adjustable mechanisms for reciprocatingthefeed dog carriers, and mechanism for oscillating the feed dog cari-iers,

6. In a sewing machine having an enclosing case, the combination with the stitch forn'iingun'eans, of a feeding mechanism comprising two feed dog carriers, independently adjustable mechanisms for reciprocat-' ing the feed dog carriers andmeans'connected with the carrier reciprocating mechanisms and extending to the exteriorof the I loo enclosing case for varying the action of said reciprocating mechanisms. ,7

I 7. In a sewing machine the combination with the stitch forming means, of a feed: ing'm'echanism comprising a feed dog car rier, mechanism for reciprocating the carrier in rectilinear paths, and mechanism for os-'- cillating the carrier on an axis parallelwith its paths at the ends of its reciprocating movements. v

8. in a sewing machine the combination with the stitch forming means, of a feeding mechanism comprising two oscillatory and .reciprocatory feed dog carriers, one carrier being fitted to the other, so said carriers may be reciprocated independently but the oscillation of one on its longitudinal axis will oscillate the other.

9. in a sewing machine the combination with the stitch forming means, of a feeding mechanism comprising a reciprocating front feeddog, a reciprocating rear feed dog, and means for oscillating the dogs on a fixed axis at the ends of their reciprocating movements.

10. In a sewing machine the combination with the stitch forming means, of a feeding mechanism comprising a front feed dog, a rear feed dog, and means for oscillating the feed dogs coincidently on an axis parallel with the line of feed of said dogs.

11. in a sewing machine the combination with the stitch forming means, of a feeding mechanism comprising a feed dog carrier having a cylindrical under surface and an angular cavity in its upper surface, feed (log carrier having anangular under surface and a cylindrical cavity in its upper surface mounted on the first mentioned feed dog carrier, mechanism for reciprocating the feed dog carriers independently, and mechanism for oscillating the feed dog carrirs.

12. In a sewing machine the combina ion with the stitch forming means, of a feeding mechanism comprising a feed dog can ricr having a cylindrical under surface and an angular cavity in its upper surface, a feed dog carrier having an angular under surface and a cylindrical cavity in its upper surface mounted on the first mentioned feed dog carrier whereby the oscillation of one carrier on its longitudinalaxis will oscillate the other carrier on its longitudinal axis, and mechanism for reciprocating the feed dog carriers independently.

13. in a sewing machine the combination with the stitch forming means, of a feeding mechani m comprising oscillatory and reciprocatory feed dog carriers, a bell crank lover connected with each feed dog carrier, an adjustably mounted bell crank plate connected with each bell crank lever, a yoke connected with said plates a cam for reciprocating the yoke, an oscillatory fork engaging one of said carriers, and a cam for oscillating said fork.

1% in a sewng machine the combination with the stitch forming means, of a feeding mechanism comprising reciprocatory feed dog carriers, a bell crank lever connected with each feed dog carrier, an adjustably mounted bell crank plate connected with each bell crank lever, a yoke engaged with said plates, and a cam for reciprocatinglthe yoke.

15. In a sewing machine the combination with the stitch forming means, of a feed mechanism comprising a feed dog, a lever engaged with said dog for reciprocating the same, a cam and cam shaft, a yoke engaged by said cam, and a link connecting said yoke and lever, said link having an arbor mounted in an adjustable support.

16; in a sewing machine having an enclosing case, the combination with the stitch forming means, of a. feeding mechanism comprising a front feed dog carrier, a rear feed dog carrier, independently adjustable mechanisms for reciprocating said feed dog carriers, a cam and cam shaft for actuating said reciprocating mechanisms and means accessible from the exterior of the casing for varying the movements of said feed dog reciprocating mechanisms.

17. In a sewing machine the combination with the stitch forming means, of a feed mechanism comprising a feed dog, a lever engaged with said dog for reciprocating the same, a cam and cam shaft, a yoke engaged with said cam, link connecting said yoke and said lever, and a tapered arbor supporting said link, said arbor being eccentrically mounted in rotatable support.

18. in a sewing machine the combination with the stitch forming means, of afeeding mechanism comprising a front feed dog carrier, a rear feed dogcarrier, one carrier fitting within the other, independently adjustable mechanisms for reciprocating said carriers, mechanism for oscillating the carriers, and a single cam and cam shaft for actuating said reciprocating and oscillating mechanisms.

19. In a sewing machine the combination with the stitch forming means, of a feeding mechanism comprising a feed dog carrier, mechanism for reciprocating the feed dog carrier, mechanism for oscillating the feet dog carrier, and a single cam for actuating said reciprocating and oscillating mechanisms.

20.111 a sewing machine the combination with the stitch forming means, of a feeding mechanism comprising a feed dog carrier, a yoke, link plate and lever for reciprocating the feed dog carrier, a fork for oscillating the feed dog carrier, and a single cam for actuating said yoke and fork.

21. In a sewing machine the combination with the stitch forming means, of a feeding mechanism comprising oscillatory and reciprocatory feed dog carriers, a bell crank lever connected with each carrier, an adjustably mounted bell crank plate connected with each bell crank lever, a yoke connected 'ith said plates, an oscillatory fork engaging said carriers, and a cam for reciprocating said yoke and oscillating said fork.

22. In a sewing machine the combination with the stitch tormmg means, of a feed mechanism comprising a feed dog, a lever engaged with said dog for reciprocating the same, a cam and cam shaft, a yoke engaged with said cam, a link connecting the yoke and lever, a rotatable cylinder, an arbor for said link eccentrically mounted in the cylindeiyand means for turning the cylinder.

23. Ina sewing machine the combination with thestitch forming means, or a. feed mechanism comprising a feed dog, a lever engaged with said dog for reciprocating the same, a cam and cam shaft, a yoke engaged with said cam, a link connecting the yoke and lever, a rotatable cylinder, means for turning the cylinder, said cylinderand turning means being trictionally held in the casing, and an arbor for said link eccen'tric'ally mounted in the cylinder.

24. In a sewing machine having a work plate the combination with the stitch torming means, of a feed mechanism comprising a frontfeed dog, a rear teed dog, mechanism for reciprocating the feed dogs longitudinally, and mechanism for oscillating the feed dogs on their longitudinal axes, the center of oscillation o the feed dogs being above the work'plate.

25. In a sewing machine having a workplate, the combination with the stitch forming means, of a feed mechanism comprising a front feed dog, a rear'feed dog, mechanism for reciprocating the feed dogs longitudinally, and mechanism for oscillating the feed dogs on a common longitudinal axis. 26; In asewing machine the combination with thestitch forming means, ot a, feed mechanism comprising two independent feed dogs, mechanism'for reciprocating the teed dogs longitudinally, andmechanism for os'- cillating the feed dog's transversely at the ends of their reciprocating movements.

' 27. In a sewing machine the combination with thestitch forming means, of a feed mechanismcomprising two independent feed dogs, mechanisms for reciprocating the vfeed dogs longitudinally, means for varying the,

reciprocating movements of the feed dogs independently of each other, and mechanismfor oscillating the feed dogs transversely at the ends of their reciprocating movements.

28. In a sewing machine the combination with the stitch forming'means, of a feed mechanism comprising two independent feed dogs, mechanism.forreciprocating the feed catingthe teed dog longitudinally, and.

mechanism for oscillating. the feed dog transversely, said reciprocations and o-scillations being so related that the forward and return movements of the dog are in different horizontal and vertical planes.

SAMUEL W. AVIS,

dogs longitudinally, means for varying the 

